Linear ion traps with the feature of high sensitivity are widely utilized in mass spectrometers. Among such linear ion traps, a linear ion trap type comprised of four rod electrodes capable of trapping (trap capacity) a large quantity of ions within the interior at one time compared to 3-dimensional quadrupole ion traps of the related art and capable of high sensitivity analysis is in wide use.
Patent literature 1 discloses a method for selectively ejecting ions by mass in a direction orthogonal to the rod electrode from a slit formed in the rod electrode after having accumulated the ions in a linear ion trap. Patent literature 1 also discloses a method for generating ions within the linear ion trap by injecting electrons into the interior of the ion trap. A toroid linear ion trap is also disclosed.
Patent literature 2 discloses a method for selectively ejecting ions by mass along the axial direction of the rod by utilizing a fringing field generated between the end electrodes and rod electrodes, after accumulating ions in the linear ion trap and carrying out operations such as isolation and dissociation.
Patent literature 3 discloses a method for mass-selectively ejecting ions along the axial direction of the rod by utilizing a DC field generated among the wire electrodes after accumulating ions in the linear ion trap and carrying out operations such as isolation and dissociation.
Patent literature 4 discloses a method for forming rod electrodes for a linear ion trap comprised of planar electrodes. Patent literature 4 further discloses a method for mass-selectively ejecting ions radially after injecting electrons from the radial direction to generate ions in the interior of the linear ion trap.
Patent literature 5 discloses a method for selectively ejecting ions by mass along the radius after causing an electron trapping-dissociation reaction by injecting electrons into the interior of the linear ion trap to react with the ions inside the linear ion trap.